1. Field of the Disclosure
The present disclosure relates generally to managing bandwidth and/or data traffic for telecommunication and computing networks. Particularly, the present disclosure relates to detecting oversubscription and measuring latency for a network.
2. Description of the Related Art
Effectively deploying multiple devices in a network environment has become an increasingly complex task as transmission data rates, processing speeds, and storage capacities continue to increase. For instance, storage area networks (SANs) are specialized high-speed networks or subnetworks, referred to as fabrics that connect computer systems, control software, and/or storage devices over the fabric. SANs, as specialized high-speed networks or subnetworks, interconnect and share a group of storage devices with one or more servers and/or hosts. To access the storage devices, a server and/or host sends out block level access requests, rather than file-level access, to one or more storage devices within the pool of storage devices. Thus, by using SANs, each of the servers and/or hosts may access the shared pools of storage devices as if they are locally attached to the server.
Data rates and throughput of SAN switches, such as a Fibre Channel (FC) switches, also continue to improve. SANs are generally configured such that a single device, such as a server or a host, is connected to a single switch port. Currently, SAN switches are configured to commonly support data rates up to 16 gigabits per second (Gbps) and in some instances up to 32 Gbps. However, even with improvements in SAN data rates, SANs may still encounter performance issues for a variety reasons. For example, servers or hosts typically include multiple computing systems, such as virtual machines (VMs), that could complicate data processing and data transfers that eventually result in device slowdowns and/or back pressure. Additionally, most SANs generally have multiple flows traversing over a single link and/or multiple network flows from multiple devices (e.g., hosts) to a single storage device that could cause bottlenecks at several different points within the SANs.
Situations where multiple devices compete for a link's bandwidth often result in poor response times and other performance related issues. For instance, performance and stability issues can arise when hosts and/or storage devices accept frames at a rate lower than an expected offered rate. Accepting frames slower than the expected offered rate can create backups in the fabric that cause multiple unrelated flows to have input/output (I/O) failures or performance drops. In particular, the performance and stability issues can occur when hosts and/or storage devices send more traffic than the capacity and/or speed of the link can handle. For example, hosts can request (e.g., transmit read instructions) more data from multiple storage devices than a switch's and/or a host's port speed. Alternatively, multiple hosts in combination could transmit more data (e.g., write commands) to a storage device than a switch's and/or a storage device's port speed. Unfortunately, accurately detecting when oversubscription can cause performance and/or stability issues may be difficult because oversubscription in a network can occur in and/or for a relatively short time period and different devices (e.g., servers and/or storage devices) possibly have different I/O sizes and response times.